Question 552716
The function is:
{{{h(t) = -4.9t^2+h[0]}}} which allows you to calculate the height (in meters) of of an object dropped from an initial height of {{{h[0]}}} as a function of time (t in secods).
When the object (pebble) reaches the ground, h = 0, so substitute this  and t = 3 into the equation and solve for the corresponding value of {{{h[0]}}}.
{{{0 = -4.9(3)^2+h[0]}}}
{{{h[0] = 44.1}}} meters.